5. The Structuring of Beliefs. Are Many Opinions Random? (re Converse) GV917.

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Presentation transcript:

5. The Structuring of Beliefs. Are Many Opinions Random? (re Converse) GV917

Political Knowledge One way of examining if people reply to questions at random because they are ill- informed is to ask them knowledge questions Political Knowledge questions indicate the extent to which people are actually ignorant about politics – and hence may have non- attitudes A battery of Knowledge questions were asked in the 2001 British Election Study

Knowledge Questions in the 2001 British Election Study TrueFalseDon’t Know Polling Stations close at 10pm on Election Day The Conservative Party policy is that Britain should never join the Euro The Liberal Democrats favour a system of proportional representation for Westminster Elections The minimum voting age in Britain is Unemployment has fallen since Labour was elected in Only taxpayers are allowed to vote in general elections 3943

Knowledge Questions in the 2001 BES On average 74 per cent of respondents gave the correct answer They were much more likely to give the correct answers about electoral arrangements (87%) than about party policies (61%) However, there is not much evidence of complete ignorance of politics in the data – random guessing would produce a Normal Distribution centred on 3 correct answers

The Distribution of Political Knowledge in 2001 (Mean = 4.4)

Political Knowledge, Age and Sex in 2001 AgeKnowledge Scores Up to Sex Male4.7 Female4.2

Political Knowledge and Work Status in 2001 Work StatusKnowledge Scores In Paid Work4.6 In Full-time Education4.2 Unemployed3.9 Retired4.4 Looking after the Home3.9

Political Knowledge and Occupational Status in 2001 Occupational StatusKnowledge Scores Professionals and Managers5.2 White Collar Middle Management4.9 White Collar Clerical4.6 Skilled Manual4.3 Semi-Skilled Manual4.0 Unskilled Manual3.8

Political Knowledge and Education in 2001 EducationKnowledge Scores Still in School or younger or older5.0

Conclusions Political Knowledge is not that high – with a mean score of 4.4. On the other hand it is far from being random, since the distribution of scores is skewed heavily to the high end Some people undoubtedly guessed some of the answers – but only 14 per cent got a score of 3.0 – which is expected if people are guessing

Are Attitudes Stable Over Time?

Attitude Stability over time – the case of British Membership of the Euro in 2001 How Much Do Attitudes to the Euro Change over Time? This is tricky for most people because it is a complex issue and experts disagree This became an election issue in 2001 with the Conservatives campaigning on a platform of ‘Save the Pound’ The Liberal Democrats campaigned to join the Euro more or less right away Labour campaigned on a promise to join if the conditions were right

Attitudes to Joining the Euro just before the General Election of 2001 – pre election survey

Attitudes to Joining the Euro just after the General Election of post election survey

Changes in Attitudes to the Euro during the election of 2001 There were clearly some changes in attitudes to British membership of the Euro which occurred during the campaign 45 per cent said join immediately or if the conditions are right before the election, and 42 per cent said this after the election But these are the net figures and hide a lot of gross turnover in opinion

Stability of Attitudes over Time – The Row percentages in a Table

Findings? Only 44 per cent of the who supported joining before the election also supported this policy after the election 64 per cent were consistent in saying that Britain should join if the conditions are right 44 per cent were consistent in waiting for 4 to 5 years 61 per cent ruled out membership in principle

The Extent to which people were consistent over time – the total percentages in a table

Findings? 55 per cent of respondents remained consistent between the two waves of the panel survey – 45 per cent were inconsistent We see this from the main diagonal of the table But ‘Definitely Join’ and ‘Join if the conditions are right’ are not that different. Are people really being inconsistent if they move from one of these categories to the other?

How Can this be explained? One explanation is that there are a lot on non-attitudes and these are the 45 per cent of respondents who change their minds Another explanation is that there are some non-attitudes, but measurement error accounts for a lot of this. One example, of measurement error is people shifting one category between waves of the survey – they are not responding randomly, but rather probabilistically.

A Recoded Version of the Table

Probabilistic Responses In the revised version of the table 65 per cent are consistent rather than 55 per cent The really inconsistent people are those who move from join to don’t join. These make up only just over 5 per cent of the sample Some may be answering at random, but others may have genuinely changed their minds in response to the campaign

Conclusions Some people clearly do answer at random, since switching right across the spectrum is clearly not likely to be a rational decision However, switching between adjacent categories is not so unlikely. So when measurement error is taken into account the randomizers may not be that large a group Knowledge of politics is limited, but it is clearly a long way from being zero with people just guessing the answers In addition ‘useful’ knowledge such as when the polling station closes is quite high. Knowledge of party policies may be less useful and so it is less important to people

An Alternative - Collective Opinions (see Page and Shapiro) They argue that attitudes are neither perfectly formed or random, but are derived from some underlying values and beliefs New information will push the individual’s preferences back and forth over time – but this might be the product of uncertainty as much as randomness Each individual will have a true long-term preference which can be observed by sampling people over time

Collective Opinions (see Page and Shapiro) If this is true then at any given moment the public as a whole will have real collective attitudes – but it is defined on average Random deviations will occur away from the average for any one individual – but collectively the public will have a ‘rational’ ie. Meaningful opinion. This averaging out process results from the law of large numbers

Condorcet ‘Jury’ Theorem More than two centuries ago Condorcet demonstrated that if a number of individuals tried to answer a factual question and each had a better than 50 % chance of being correct, then a collective decision by majority vote had a much better chance of being correct than a decision by a single person Suppose an individual has a 60 % chance of being correct (and a 40 % chance of being wrong) Suppose we add two more individuals to the ‘jury’ What are their chances of being correct by majority voting?

Condorcet ‘Jury’ Theorem Note that if at least two of them vote for the 0.60 branches, they will come to the right decision. So probability of a correct decision under majority rule = =0.648 – the probability of the jury being correct has increased by when three people are on it compared with only one